1. Field of the Invention
The present invention relates to a process and apparatus for including a decoration in sheet form. In particular, it relates to including a textile material, as a medallion on the surface of a piece of plastic material, as well as a mold for carrying out this process and a piece obtained by this process.
Of course, several medallions can be included by the present process, either simultaneously or one after the other, in the same piece, which, in its turn, can be formed of one or more parts.
2. Discussion of Related Art
Such pieces are, for instance, known in the automobile industry. Thus, certain door fittings present visibly, that is to say from the interior of the vehicle, the aspect of a piece of plastic material having, inserted in its surface, or, stated differently, as a medallion, a decoration in sheet form, for instance of fabric, at the level of the arm rest. Plastic material also serves as support for the sheet decoration, that is to say forms the volume of the arm rest proper, and is therefore not directly visible. Another insert can form the bottom of the door.
Generally, the peripheral part of plastic material, without decoration other than its own surface finish and the medallion, formed of the sheet decoration and its plastic support material, are made separately and then assembled, either directly or later on, for instance by means of fasteners. The medallion itself is obtained by molding the plastic support material over the decoration.
Such processes entail numerous operations as well as numerous restarts between the different operations, which result in a number of drawbacks.
There has also been proposed, in British A-227 1956, a process for including a sheet decoration, particularly of textile, as a medallion in the surface of a piece of plastic material which comprises the steps consisting:
of using a mold comprising at least two parts, at least one part of which is formed of at least two elements, at least one element corresponding to the medallion and at least one other element corresponding to the periphery of the piece, around the insert; PA1 in bringing the decorative sheet onto the element corresponding to the medallion and closing the mold; PA1 in isolating, within the mold cavity, the space located below the decorative sheet from the peripheral space, using a mold the part of which comprising said elements includes at least one third annular element surrounding the element corresponding to the medallion and adapted to apply itself against the other part of the mold; PA1 in injecting plastic material in succession into the spaces thus isolated; and PA1 in ejecting the resultant piece.
This process has the drawback that the different parts of the piece are simply juxtaposed, the decoration being merely glued onto one of these parts. Thus, on the one hand, the connection between these parts is weak and, on the other hand, the decoration is fastened to the piece in a manner which is not very firm.